Measuring device



Dec. 159

A.' D- EVANS MEASURING DEVICE 2- she iheet 1 Filed May 24, 1952 Dec. 15, 1936.. A. D. EVANS MEASURING DEVICE Filed May 24, 1952 2 Sheets-Sheet 2 5 w 4 v. 2 1,: 1+ M W j u (||l. 6 I; in a r 4 29 9. w: u a W rm:

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' Q 4 NITED; STATES f d D? 1.5 1 3 2,064,467 MEASURING DEVICE- Archibald D. Evans, Warren, Ohio, assignor to The Wean Engineering Company, Incorporated, Warren, Ohio, a corporation of Ohio Application May 24, 1932, Serial No. 613,167

I Claims. My'invention relates to the measurement of particular, to themeasurement of the length of packs being rolled in a sheet mill, although not in any way limited to such application.

In the past, it has been the practice in mills manufacturing steel sheets and tin plate to determine the gauge or thickness of hot rolled material by measuring its length. Since the sheet bars with which the sheet rolling operation is started are elongated in one direction only, the

length of the material bears .a constant relation to its thickness or gauge. measuring the length to determine the gauge is, obviously, that it is muchmore accurate and is also considerably easier.

The prior method of measuring packs being rolled is by the use of a graduated steel measuring rod which is applied directly to the packs, generally after they have been finished. This method is useful only as a check to insure that the pack has been sufliciently elongated. It does not guard against insuflicient or excessive elongation of the'pack, since the adjustment of the rolls and the resulting elongation is controlled entirely by. the roller or operator in charge of the mill.

based upon his experience and observation. The objection to insuiiicient or excessive elongation of the pack is obvious. In most cases, purchasers of sheets insist that the product gauge between certain narrow limits and any variation therefrom results in rejections. Insuflicient or exces-v sive elongation, however, is objectionable for other reasons also. If a pack has been subjected to excessive elongation, the sheets thereof,

will not only gauge below the desired thickness but the scrap losses represented by the sheared ends of the pack are increased or, in other words, a smaller proportion of the useful metal is included in the finished product. In. the case of insuflicient elongation of thepacks, the scrap loss is aminiinumbut the gauge is heavy. The chief objection, however, is that the required size of sheets cannot be sheared from a short pack. The only alternative, therefore, is to shear the pack into sheets of the next smaller standard size and stock them'in the hope that t fi can be disposed of on some other order. Generally, sheet mill rolling schedules are based onthc orders for theiinished product; in otherworis, it is a not usual to roll different sizes of sheets for stock. It is thereforedesirable to convert the tions of the purchaser's order. This is particu- The advantage of larlyimportant because steel sheets-are sold on a tonnage basis and anything which decreases the percentage by weight of the raw material converted into a salable finished product represents a'direct loss. The tendency on the part of the roller, furthermore, is to over-elongate the packs because he is penalized more severely for "cut-downs" resulting from short packs than for excessive scrap resulting from excessively elongated packs.

The old method of measuring pack lengths as a final check is also undesirable because of the 7 time delay in the mill operation which it necessitates. For this reason, the rollers do not check every pack length because they are paid on a tonnage basis and it may happen that the lengths of successive packs vary widely without any check whatever being. made until a pack is cold and ready to be sheared. If a check of the pack length indicates it is too short, it can be elongated slightly by repassing itthrough the rolls after it has cooled sufliciently to prevent excessive elongation. The time lost while waiting for the pack to cool is often suflicient to roll two or three other packs.

tionsin the thickness of the rough rolled breakdowns forming the packs fed to the finishing mill are inevitable. These several variables make it impossible to establish any standards of practice and as a result, it has been necessary for the roller to rely on his skill and experience to A approximate as closely as possible the'desired dimensions of the pack. The present invention makes it possible for the roller to know exactly the length of the pack at every step in the finish rolling operation. All guess work and approximation is thus eliminated. No lost time. is necessary to check the pack length and the roller is properly for the next pass so that any deficiency or excess of length produced by the preceding pass can be compensated for, h 3 r i In accordance with the invention, I provide means-whichmoves at a speed proportional to the peripheral speed of the mill rolls for theinterval during. which the material is between the rolls. Thus an accurate measurement of the pack length r is provided for the roller by means of an indicat- 4" enabled after each pass to set his screwdown a clutch members I9 and 20.

ing dial which may be provided with markers to indicate the proper length of pack after each successive pass. by means connected with the main mill drive and is operatively associated therewith during the actual rolling interval by electromagnetic means controlled by the pack traversing the pass.

For a complete understanding of the invention, reference is made to the accompanying drawings illustrating a present preferred embodiment of the invention, although it is to be understood that various changes and modifications in the embodiment described may be made without departing from the scope of my broader claims. In the drawingsz- Figure 1 is a diagrammatic view illustrating the invention schematically;

Figure 2 is a front elevation of the rollers indicating mechanism;

Figure 3 is a sectional view taken along the line III-III of Figure 2 showing the drive for the indicator in plan;

Figure 4 is a sectional view along the line IV-IV of Figure -3;

Figure 5 is a sectional view along the line V-V of Figure 4;

Figure 6 is an enlarged view of a detail;

Figure 7 is a diagram illustrating the shape of a pack for a certain condition of the rolls; and

Figure 8 is a similar view showing the shape of the pack resulting from a different roll contour.

Referring now in detail to the drawings, and for the present, to Figure 1, a rolling mill is indicated in plan at ID. The rolls of the mill II] are driven through a spindle II by a main mill motor I2 geared thereto. The motor I2, in addition to driving the spindle II, drives a polyphase synchronous alternating current machine I3 which acts as a transmitter for supplying energy to a similar machine I4 operating in synchronism therewith and serving as a receiver. Both machines I3 and I4 receive excitation from a supply circuit I5; The receiver I4 is geared to a shaft I6. A coaxial shaft I1 is provided with an indicator I8. Clutch members I9 and 20 permit the shafts I6 and II to be coupled so that the indicator I8 is driven at a speed proportional to that of the rolls of the finishing mill. A clutch-opcrating magnet 2| operates through a lever 22 to actuate the movable clutch member I9. The magnet 2I is controlled by a flag switch 23 having a target 23' in the path of the packs emerging from the mill Ill. The flag switch may be located in any convenient position, preferably as close as possible to the mill.

It will be obvious from the foregoing that the shaft I6 is driven continuously at a speed proportional to that of the mill rolls through the driving mechanism described. During the interval in which a pack is between the rolls of the mill I0, the magnet 2I is energized to engage the The indicator I8, therefore, travels at a speed proportional to the peripheral speed of the mill for a time interval corresponding to that during which the pack is between the rolls. The total movement of the indicator, therefore, is proportional to the product of the peripheral speed of the mill and the time during which a pack is between the mill rolls. This product, of course, is the length of the pack which is communicated to the roller byhis merely observing the indicator. A spring 24 serves to return the indicator I8 to a predetermined initial position as soon as the clutchshifting magnet 2| is deenergized by the passage The indicating mechanism is driven of the pack out of the mill, whereby the switch 23 is opened.

A detailed description of the parts of the invention will now be given, using reference numerals corresponding to those already employed 7 to indicate similar members.

The indicating mechanism indicated generally by the numeral 25 comprises a face plate .26 having a glazed dial 21 with which the indicator I8 cooperates. As shown more particularly in Figure 6, the dial rim is provided with a plurality of tapped holes 28 for receiving thumb screws 29 to secure adjustable markers 30 in different positions around thedial. The face plate 26 is supported on a standard 3| and a base 32.

A bearing plate 33 forming a supporting shelf for apparatus about to be described is mounted behind the face plate 26. Below the shelf the receiver unit I4 is suspended for driving the shaft I6. The shaft I6 is journaled in bearings 34 and is provided with a gear 35 meshing with a pinion 36 on the shaft of the receiver unit I4.

The clutch member I9 is splined to the projecting end of the shaft IE, as is a collar 31. A spring 38 connects the collar and the clutch member. The lever 22 is provided with a fork 39 engaging the collar 31. The lever 22 is pivoted at 40 on the plate 33. A tension spring 4I normally maintains the lever 22 in clutch-retracting position. The clutch-shifting magnet 2I operates a yoke 42 connected to the lever 22 by a link 43. The indicator shaft I1 is journaled in bearings 44 coaxially with the shaft IS. The clutch member 20 is pinned to the shaft H for cooperation with the clutch member I8. The indicator I8 is secured to the shaft I! by means of abushing 45. The resetting spring 24 has one end secured to a bushing 46 on the shaft II, the other end being adjustably engaged between an abutment 41 on the rear of the face plate 26 'and a set screw 48 threaded thereinto.

A cover 49 for the mechanism driving the indicator is preferably removably attached to the rear of the base plate 26.

Having described the apparatus constituting an embodiment of the invention, the method of operation will now be briefly reviewed and the advantages of the invention in actual practice pointed out.

When a pack of sheets has been heated to the proper rolling temperature, it is advanced to the finishing mill I0 and entered therein. The rolls of the mill ID are driven continuously at a substantially constant speed by the motor I2. The-pack is preferably entered between the rolls and automatically returned thereover after the first pass for successive reductions by automatic means, such as the feeding and catching tables described and claimed in the co-pending applications of McIlvried, Moore and Peterson, Serial No. 581,202., filed December 15, 1931, for Rolling sheets and packs, and Wean and Evans, Serial No. 605,599, filed April 16, 1932, for Feeding and catching table now Patent #1,9'74,403, Sept. 18, 1934. In that case, the flag switch 23 may be actuated by the same mechanism which operates the switches controlling the movements of the catching table. This mechanism is located on the end of the table as close to the rolls as possible. I

.The shaft I6 of the indicator mechanism, of course, turns constantly at a speed proportional to that of the main mill drive and the clutch members I9 and 20 are normally disengaged by the spring 4I. As soon as the pack enters the mill, however, and the leading end thereof closes the flag switch 23, the clutch-shifting magnet M is energized so that the shaft" I1 is driven with For different dimensions of finished product,

the roller knows approximately what length the packs should have at the end of each successive pass. He will, therefore, adjust the markers 30 around the rim of the dial 21 to conform to the desired lengths of packs after each of the necessary passes. It will be the'rollers aim, furthermore, to adjust his screwdown so that the indicator l8 will advance into alignment-with the marker corresponding with the pass being effected. As long as the flag switch 23 is closed,

the magnet 2| remains energized and the, indicator I8 movesaround its dial.

As soon as thepack passes completely out of the rolls and the switch ,23 is opened, however, the magnet 2i is deenergized. The clutch members I9 and are thereupon disengaged and the retracting spring ll, which is wound up as the indicator l8 advances, operates to reset the indicator to the zero position illustrated at Figure 2., which is determined by any suitable stop. By observing the indicator l8 as the pack passes out of the rolls, the roller can determine whether the length of the pack after that particular pass is equal to or greater or less than'the pack length which he has determined by experience should be produced after such pass to give the desired character of finished product. If the pack length measures up short, the roller will adjust the rolls for the next pass accordingly so that any deficiency in pack length will'be compensated in the next pass. The same compensation can be made if, after one pass, the pack length is greater than it should be.-

The roller thus has definite information as to the length of each pack aftereach pass through the rolls and this informationis obtained merely by glancing at the indicator l8 as the pack emerges from the rolls. No time-consuming measurements need be made and production is not interfered with in any way.

While it is impossible, for obvious practical reasons, to position the flag switch 23 at the exact center of the roll pass, this fact is not material since, with the automatic feeding and catching tables above mentioned, the pack travels at the same speed before entering and after leaving the rolls as it doeswhile'between the rolls. Other types of switches could be employed, for example, one actuated by the elevation of the top roll upon theentrance of the pack between the rolls.

The switch 23 is preferably not closed by reverse movement of the pack over the top roll of the mill l0, although reclosure of the switch may be desirable to repeat the indication of the pack length in case the roller failed to note the indicator on the emergence of the pack from the mill. As an alternative, the indicator might be provided with an idler needle actuated in the forward position by movement of the indicator I8 and reset manually after the completion of the work on any one pack. In this way,-the points to whichthe indicator l8 advances after successive passes would be recorded by the idler needle in case the roller should lose sight of the instantaneous position of the indicator 18 before resetting thereof after each pass.-

It will be apparent that the invention described above is characterized by numerous advantages. One of these, and a very important one, is the a possibility of calibration of the indicator by the roller to determine what the successive indications should be after each pass. It is impossible, as a practical matter, to permanently calibrate the indicator because of the variations in the diameter and, therefore, the peripheral speed of the mill rolls, and the time necessary for operation of the mechanical equipment after the 010- .sure or opening of the fiag switch. The indicator is calibrated by the roller, by actually measuring thepack lengths after each pass for at least onepack. Theroller knows approximately what magnitude of reductions in gauge are feasible for different classes of products and by measuring the pack lengths after each pass, the markers 30 can be adjusted around the rim of the dial 2! to serve as a guide for the screwdown adjustments prior to successive passes for all the other packs. After the first calibration, of course, slight corrections either way in the marker settings may be made if subsequent observation indicates that recalibration is advisable. During the progress of a particular order through the finishing mill, furthermore, an occasional check by actually measuring a finished pack length will be suflicientprotection against cumulative errors.

The possibility of recalibration isalso important when it is considered that the maximum length of packs differs with different conditions of the contour of the roughing mill rolls. This contour changes very slowly and, since packs are finished in the order in which the breakdowns are rolled, the change may be compensated for by recalibration, as above described. Figure '7, for example, illustrates the shape of a pack for a certain contour of the roughing rolls. The

dimension A, of course, represents the maximum usable length of the pack and this dimension -must conform to the required finished length of the pack. The flag switch controlling the indicator is preferably closed until the extreme end of the pack has passed thereover because the trailing end must clear the roll surface. on tilting of the catching table. If the packs have the shape shown in Figure -7, therefore, the roller must see that his indicator registers a greater length than is actually required of the.

, compensate for this by proper allowance in the calibration of the indicator dial.

Whether the indicator will show the usable length of the pack or the actual length of the for by the order being rolled is avoided. Overelongation is likewise avoided and the scrap loss is decreased, with a corresponding increase in the tonnage yield of salable product.

Although I have illustrated and described herein but a single preferred embodiment of the invention, it will be recognized that numerous changes in the details of the invention disclosed may be made without departing from the scope of the appended claims. While the invention has been described with reference to the measurement of packs of sheets being rolled, it is obvious that it may also be utilized for the measurement of other types of material during movement thereof.

I claim:

1. Apparatus for measuring the length of continuously advancing packs comprising an indicator, a drive shaft therefor, means for driving said shaft at a speed proportional to that of the pack, a clutch on said shaft for engaging said indicator, a clutch shifting magnet, a flag switch operable by engagement of a pack therewith for controlling said magnet, and means rendered effective on movement of the indicator to restore it to initial position when released by the clutch.

2. The combination with a rolling mill having work rolls and driving mechanism therefor, of an indicator, a driving shaft, connectible to said indicator, means for driving said shaft at a speed proportional to that of the mill, means actuated by the material in its passage through the mill for connecting said shaft to said indicator for a time proportional to the length of the material,

I and means rendered effective on movement of the indicator to restore it to its initial position when disconnected from the driving shaft.

3. The combination with a rolling mill, of means for indicating the length of material passing therethrough, comprising an indicator, means controlled by the passing material for actuating said indicator for a time proportional to the length of the material, and means effective on said indicator continuously, to return it to its initial position after each operation by said actuating means.

4. A measuring device for strip material comprising an indicator, continuously driven means for actuating said indicator, a clutch for conmeeting said actuating means to the indicator, means actuated by the passage of material past a predetermined point for causing engagement of said clutch, and means effective continuously to reset the indicator at its initial position on' disengagement of the clutch.

5. The combination with a rolling mill, of means for indicating the length of material passing therethrough, comprising an indicator and a shaft for actuating said indicator, means controlled by the passing material for actuating said shaft for a time proportional to the length of the material, and means effective on said shaft continuously, to return it to its initial position after each operation by said actuating means.

ARCHIBALD D. EVANS. 

